The elderly and healthcare workers could be the first in line for the breakthrough Covid-19 vaccine that has proven to be more than 90 per cent effective.

German pharmaceutical company Pfizer announced the vaccine could potentially be available within weeks as it plans to apply for emergency approval to use the vaccine.

It comes after the day was declared a “great day for science” as the vaccine tested on 43,500 people had no safety concerns raised in its final stages of testing.

The analysis was carried out after 94 confirmed cases of Covid-19 were found among those taking part in the trial.

The Joint Committee on Vaccination and Immunisation (JCVI) said care home residents and staff were among those who should be given the jab first.

The prioritisation for other people is linked to their age and risk.

The committee examined data on who suffers the worst outcomes from coronavirus and who is at highest risk of death.

The interim guidance says the order of priority should be:

• Older adults in a care home and care home workers

• All those aged 80 and over and health and social care workers, though they may move up the list

• Anyone 75 years of age and over

• People aged 70 and over

• All those aged 65 and over

• High-risk adults under 65 years of age

• Moderate-risk adults under 65 years of age

• All those aged 60 and over

• All those 55 and over

• All those aged 50 and over

• The rest of the population, with priority yet to be determined.

But the JCVI stressed this list was “not considered definitive” as more data is still being collected on at-risk groups.

The Government has procured 40 million doses of Pfizer/BioNTech’s vaccine, with 10 million doses being manufactured and available to the UK by the end of the year – if the vaccine is approved by the regulators.

Prof Horby, professor of emerging infectious diseases and global health in the Nuffield Department of Medicine at the University of Oxford, said: “This news made me smile from ear to ear.

“It is a relief to see such positive results on this vaccine and bodes well for Covid-19 vaccines in general.

“Of course we need to see more detail and await the final results, and there is a long, long way to go before vaccines will start to make a real difference. But this feels to me like a watershed moment.”

Professor Fiona Watt, executive chair of the Medical Research Council, said: “This is very encouraging news – and provides grounds for optimism that other vaccines will also show benefits.

“What really strikes me though is the fantastic contribution of the many volunteers who have taken part in the trial, including over 40 per cent from diverse backgrounds. Without their altruism, the trial could not have gone ahead.”